There is a need for disinfection and sanitization of a large number of types of bodies of water, including, for example, cooling water systems, pasteurizing systems, waste water effluents, pulp and paper mills, swimming pools, hot tubs, spas, fountains, water attractions, oil fields, air washers, fire reservoirs, and evaporative condensers. In these bodies of water, the growth of bacteria, fungi, algae, slime, and mollusks are undesirable and/or detrimental. Unfortunately, these systems often have ideal conditions for growth of these organisms. Many methods for preventing and killing such growths have been devised.
Many of these methods for sanitizing bodies of water have a drawback. For example, the use of trichloroisocyanuric acid by itself as a sanitizing chemical poses problems because trichloroisocyanuric acid reverts to chloride ion and cyanuric acid upon performing biocidal chemistry; cyanuric acid can build up to levels where the hypochlorite is rendered less effective, causing the phenomenon known as "chlorine lock." Halogenated hydantoins, which are common water-sanitizing chemicals, are notorious for their dusts, which are irritating to human mucous membranes. Hypobromous acid is a desirable biocide because it is known to be more effective than hypochlorous acid at the conditions of most bodies of water needing sanitization. Hypobromous acid is usually produced in situ due to its instability in water. Methods to produce hypobromous acid in situ have included the use of a bromide ion source and an oxidant, such as hypochlorous acid or hypochlorite ion. Further, it is known that the hypobromous acid (or whatever biocidal bromine species is formed) may be stabilized in the presence of a suitable chemical. For example, Mines de Potasse, in GB 1,358,617, use dimethylhydantoin to prolong the life of the biocidal bromine species; the biocidal bromine species only remained for several hours.
Thus, it is clear that there are several unmet needs in known water sanitization methods. A method which either prevents or circumvents chlorine lock is needed. A need exists for a method of dosing halogenated hydantoins to a body of water which minimizes the exposure of the human handler to the halogenated hydantoins. Additionally, a method for stabilizing biocidal bromine species for longer periods of time is also desirable.